Music-loving optimists, take heart: The rain could stop by the time Amy LaVere takes the stage at 6 tonight to begin the Memphis in May Beale Street Music Festival.

Pessimists, take note: Lightning, hail and tornadoes could cross the river into Memphis this evening.

Either scenario is possible, according to area meteorologists, who are watching the cluster of storms that produced fatalities today in Arkansas, along with quarter-size hail.

Whatever happens, Tom Lee Park — which opens to festivalgoers at 5 p.m. — will be muddy and messy tonight. But Memphis in May officials say the show will go on as scheduled, barring dangerous weather.

Cancellations or delays will not occur unless the weather at showtime is judged to be a threat to the safety of the performers or festgoers, due to strong lightning, extremely high winds or other dangerous conditions, said Diane Hampton, Memphis in May executive vice president. Until then, festival officials are keeping their fingers crossed.

The Memphis area remains under a tornado watch through 8 p.m., issued by the National Weather Service.

According to the weather service, a tornado watch means that “conditions are favorable for the formation of tornadoes and severe thunderstorms in and close to the watch area. Persons in the watch area can continue with their day-to-day activities, but should keep an eye to the sky for threatening weather.”

Severe thunderstorms are expected until 6 p.m., according to Richard Okulski of the weather service. However, “subsequent thunderstorm development” could follow, even if the current system blows through by early evening, he said.